The speaker looks back at how time makes us forget who we once were, and the poem reads like a regretful confession. The "child we were" is pictured as something we left behind in a "white room," which, together with the later mention of the E.R., suggests a hospital where that innocent self was dumped and neglected. The child seems to stand for our early, unguarded self, the part of us that was sacrificed when we went out to fight our own battles and face a "Scarecrow," perhaps a fear or false threat. Under the "gaze and prod of peers," we gave in to pressure and let that younger self suffer, almost to "death row." Now it lies bedridden and afraid of dying.
The mood is sad, guilty, and a little bleak. Images like the "dark old moon" and the sterile hospital room make the loss feel cold. The last line, "What we once were is now so very far," ends on distance, as if going back is nearly impossible. The wording is sometimes awkward, but the regret comes through clearly.